Mold core



Feb. 22 5 1927.

. 1,618,647 Sa. FLAM MOLD CORE mled Oct. 8, 1923 ,2... FIE I.

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32 l] FIEL-4 9 FIEL . /Nvf/vro/e epen Flam A TTOBNEY vPatented Feb. 22, 1927.

STEPHEN FLAIVI, OF I/VALNUT PARK, CALIFORNIA, ASNSIGNOR TO SUPERTILE MACHIN- ERY CORPORATION, OF LOS ANGELES, CALIFORNIA, A CORI.-ORATIONk OF CALI- FORNLA.

Morin conn.

Application filed vOctober 8, 1923. Serial` No. 667,243.

'This invention relates to a. mold for forming articles from plastic material, and more particularly to va core construction for use inv concrete or cement molds for building mate-` 5 rialsl` or for pipes.

In case blocks arecast, such cores are necessary to secure the requisite degree of lightness and saving in material; while in pipe molds, cores of course serve to define the inner surface of the pipes.

`0 In order to permit the cores' to be readily assembled in the molds for pouring, and to withdraw them after the casting is set, these cores are often made collapsible. It is one of the objects of myfinvention to provide ,5 suoli a core that may readily be expanded ments of the mold, each compartment form-- in'g a block mold. A rIhese compartments may be formed by the aid of strips of sheet metal vor thelile, through which the cores extend. In the past,such lcores were held in place by the aid of wedges or the like which servef to yexpand the mold, whereby they were tightened 'within the apertures'inr the strips.

SuchA proce-ss of assembling is tedious,andlit isy another object of my invention toprovide a core in which the necessityl of Vdriving wedges .is entirely obviated, and-insteada sino-le movement is all that is necessary to expandor tocontract the core.- A Y I Still another object of my invention is to provide a core constructionv such that it compensates automatically for any slight irregularity in the mold, as forfexample where the plates through which the cores pass and which form the mold compartment-s, are not accurately alined behind one'anothenor are regularitiesmay be occasioned, and are often caused, by the haidfusage that the molds "receive Vithout some-form of compensatthat'I aim'to correcta- Y A `Further objects of my invention're'side in 'ccrtain combinations of mechanical ele' twisted from 4their original form. Such i1 Y this condition ments, which are described in the following description, and pointed out with particularity in the appended claims.

Y55 The invention itself is exemplified in a single embodiment as applied to aY block or tile mold il-j lustrated in the acompanying drawings. It

is to be' understood however that I donot d esire to be limited to this embodiment,

since the invention as expressed in the claims may beembodied in other forms also. Referring to the drawing:

Figure 1 isa top plan view of a portion of a block or tile mold utilizing my invention I Fig. 2 is a front elevation 0f theportion vinto rectangular mold compartments 11'.

Such construction is especially vradapted forv concrete block molding. Each row is formed-l by a pair of longitudinally extending plates 12 I (Figs. l an d2); these plates may be appropriately Vformed with slots 13. VThe separating. plates 14 'are correspondingly vformed with the 'iiapsf or projections 15 which extend into theslots 13. This manner since obviouslyother types of construction may be 'used to produce substantially the be assembled and dismantled'uin-'an obvious manner. Adyacent rows inthe presentin- `of Aforming the rectangular mold compartments is illustrated by way'of example only, y90

stance` are separated bya small spacefloy. v

Vthe aid lof lthel spacer strips 1 6. QThese may beof kwood or the like,"and fastened pref-- `l`erably to kone 'only ofthe-longitudinal?strips "z.

12. In "any f appropriate manner, the rows of molds are held tightly together; "and: v vfurthernfiore the entire assemblyrests onv a. f plane surface that forms tl'i'e 'bottom of the' mold.Y .-After the mold1 has Vbeen-"filled and.

the blocks setsufliciently, all of the plates 12 and 14 may be separated, and later set up for use again.

In order to economize in material and also to make the finished product as light as practicable, it is commento provide one or more cores 17 which serve to form apertures in the product. To accommodate these cores, the plates le are provided with preferably two apertures 18, through which the cores may extend. Each-of the cores pref-- erably extends through all of the plates 14 in a longitudinal row,y as clearly shown in F ig. -1. The cores 1'? in the present instancel lare substantially cireularin cross section, and formed by overlapping thev edges of a continuous strip of resilient sheet metal. This overlapping is shown most .clearly at 19 on Fig. .3. The material in the cores is so arranged that when no force is exerted thereon, the core assumes the collapsed position as shown by the bottom core 17 of F ig. 2; in this condition, its external diameter is somewhat less than that of the apertures 18 in plates 11i, whereby the cores may be readily inserted or removed from these plates. In its active position, however, the core 17 is expanded, as shown bythe top core 17 of F ig. 2. This expansion is allowed for by the overlapping portion 19. In this condition the core 17 engages tightly against the inner walls of apertures 18. l

One of the important features of my invention resides in the ease with which the contraction and expansion of core 17 may be accomplished. F or this purpose all that is necessary is to rotate a-rod 2O as by the aid of the handle'21 which is formed by bending the end of the rod 20.

In order that rotation of rod 20 may eifect this result, this rod is pivoted near one edge of the overlapped part 19. of core17, as in the bearings 22 shown most clearly in Fig. 3. These bearings are located near the Vends of the core, and inside thereof. The bear-V ings 17 may conveniently be formed integrally with the curved base V23 which extends over the overlapped portion 19, and is fastened as by rivets2et to the inside of core 17, and to the inside edge only of the overlapped portion 19. To the'other edge are fastened the bearings 25. Now in order to permit the expansion and contraction of thecore 17, itis merely necessary to provide a mechanical connection between the rodl or'shaft 2O and the members 25.V This is accomplished by a crankor link connectionfwhich in Ythis instance, includes` the cranks 26 and the linksY 27. The cranks 26 are shown as fastened to the rod 2O (Fig. 3) on the inside of the bearing members 22, and are pivoted to one endof the links 27, as by the aidV of the cotters 28. The other end of each of the links is pivotedjto its respectivebearing 25, as by the aid of the in Fig. 2.

'20 also falls under the arch.

Vresilience that it can' give a little.

' the core.

cotters 29. The links 27 are arched as shown, so as to permit the free movement oferank 26 between the two positionsshown In the upper portion of the figure, the mechanism being in the core erpanding position, the crank 26 falls outside of the arch formed by link 27; while in the lower contracting portion of this ligure, the link 2'? encompasses the crank; and rod This change in relative Vposition is accomplished by api propriate movement of handle 21.

In the expanded position of` core 17 a force due to vthe resilience of the core is transmitted through link 27 and urges crank 26` to a locking position. In order to permit the core to go to the collapsed position shown at the bottom of Fig. 2, it is necessary to rotate handle 21 in a counterclockwise direction by a slight amount over center; at least ments 26 vand 27, which form for this pur-V pose virtually a toggle connection between two peints .on the `core that are near the overlapping edge and which therefore move substantially relative to each other when the size of the core isvaried.

Although a rigid link 27 may be advantageously used, I prefer to make it of such The bowed shape of this element assists in providing` this effect. Due to this resilience, any slight misalinement or other irregularitydue to rough usage is readily compensatedffor and is taken up by it. Thus this feature is of considerable importance due tothe severe handling usually Vaccorded this Vtype 'of' apparatus, and in fact without it, the core might in ashort` time become incapable of use.

It is evident. that without some guiding device, there would be no assurance of causing the expansion and contraction to take place uniformly and without distortion of lVith my construction thisghide is very readily supplied. For this purpose both of the castings 23 areextended as at 30 to form a tongue. `One edge of this tongue 30 is adapted to enter between the pin 29 for link 27 and the Vcore metal itself, asclearly indicated in Figs. 2 `and 4. This edge is properly shouldered as at 31, (Fig. 4C) so as to provide for a track upon which the Vhead of cotter pin 29 `travels. The vertical wall 32 of the-shoulder also helps to prevent the withdrawal ofthe pin. .It is evident that with this construction` the expansion and contraction of-coreA 17 must take `place inV suchv a way as to permit the tongue 30, fastened to one edge of the core, to slide in aspace defined by stationary elements assof ciated With the other edge. Of course 'other varieties of such a construction could be designed, but it is considered unnecessary to detail these here.

The mode of operation of the entire core is evidently clear from the foregoing de scription. To insert the core in the mold apertures, it must be in the collapsed position; then by turning handle 21 in a clock- WiseY direction for about a half-turn, theV core 17 is expanded and is caused to ll the apertures 18 snugly. VAfter the plastic material is poured and set suiiiciently, the reverse process is used to free the core from the mold.

Although a block mold is disclosed in the present application, it is of course possible to utilize the invention in connection With all other kinds of cored molds, such as pipe or conduit molds.

I claim; y

1. In a collapsible core, a tubularbody capable to being expanded or contracted, and

means for expanding or contracting the Y body, comprising a pair of pivotally connected elements operating at their unconnected extremities to vary the size of the body, one of said elements being resilient as as regards its length.

2. The combination as set forth in claim l, characterized by the fact that the resilient element is a bow spring. v

8. In a collapsible core. a tubular body formed of a single piece of resilient ma.- terial With adjacent unconnected edges, and

means foi' altering the sizeof the body,

comprising a toggle link mechanism con` necting the interior of the core at two places located respectively near the opposed edges,

one 'of the links of the toggle being resilient as regards its length. d

et. In a collapsible core, a tubular body formedof a single piece of resilient material Vwith adjacent unconnected edges, and means for altering the size of the body, comprising a rotatable rod extending Within the body Vfor substantially the full length thereof,y

means for pivotally supporting it Within the body near one of the edges. a pair of cranks fastened to the rod near the extremities of the body, and bowed resilient links pivoted to the cranks and also to the core body near that edge Which'is not in direct mechanical' connection with the rod.

5. In a collapsible core, a tubular core their free extremities near the adjacent edge,

and capable When extended of expanding the core, a bearing support lforvone of the links, and an extension on said support and adjacent the inner surface of the core body,

said extension adapted to telescope, as the .Y

size of the core is varied, between the inner surface of the core and a part of the Vlink mechanism. 4 In testimony whereof, I have hereunto set my hand.

. VSTEPHEN FLAM. 

